Just bought a 90 f150 5.0 4x4 automatic.
I am having 2 pronounced issues. Before mentioning that, the truck cold starts perfectly and idles and runs great when cold. The truck also DOES NOT have the check engine light on. Now onto the issues:

1: When warmed up the truck developes a stutter/miss but only when under acceleration, it will cruise fine if not into the gas. And the heavier into the gas, the worse the issue becomes.

2: After the truck is all
warmed up and you shut it down you have to wait 5-10mins to restart it or it will not start, won’t crank at all or will be a very slow crank.

For some more information, the truck has a new battery, distributor and module, wires, plugs, coil and starter.

Look forward to some insight, thanks guys!

 

Click this, read the caption, & edit your signature:


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1: When the key is in START and the engine isn't cranking, what's the voltage on each terminal of the starter relay? Keep the meter's black probe on the battery (-) post (not the clamp around the post, but a clean spot on the post itself), and only move the red probe around.


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What do the battery terminals look like?


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2: What's the truck's maintenance history? Any damage/repairs/modifications/aftermarket options? When did this symptom appear (time/miles)? What's the spark plug gap? What's the fuel pressure? Are the engine mounts broken? Are the U-joints sloppy? Are the tires balanced? Is the pinion nut on the rear axle tight? Read this caption a few times, and then pull codes:


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Do you have a Haynes manual? Have you read it cover-to-cover at least once?


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